Diffusion-resistant dispersible yellow couplers for the production of photographic color images

ABSTRACT

A multiple-layer color photographic material containing silver halide as the photo-sensitive substance containing in the bluesensitive component layer a diffusion resistant dispersible color coupler for the formation of the yellow partial image of the following formula WHEREIN THE SUBSTITUENTS R1, X, R2 and n have the same definition as described hereinafter, which developed dye have favorable spectral properties.

United States Patent [191 Kiiffner et al.

[451 Nov. 19, 1974 DIFFUSION-RESISTANT DISPERSIBLE YELLOW COUPLERS FOR THE PRODUCTION OF PHOTOGRAPHIC COLOR IMAGES Inventors: Karl Kiiffner, Unterhaching near Munich; Hans Glockner, Pullach near Munich, both of Germany Agfa-Gevaert Aktiengesellschaft, Leverkusen, Germany Filed: Mar. 22, 1972 Appl. No.: 236,972

Assignee:

Foreign Application Priority Data Mar. 25, 1971 Germany 2114577 US. Cl. 96/100, 96/74, 260/262 R llnt. Cl G03c l/40 Field of Search 96/100 References Cited UNITED STATES PATENTS 11/1968 Yoshida et a1 96/100 3,725,072 4/1973 Yoshida et a1 96/100 Primary Examiner-J. Travis Brown Attorney, Agent, or Firm-Connoly and Hutz [57] ABSTRACT R in R1 7 7 h 2) wherein the substituents R,, X, R and n have the same definition as described hereinafter, which developed dye have favorable spectral properties. I

3 Claims, N0 Drawings This invention relates to color couplers which react with suitable developer substances of the p-phcnylene diamine type to form yellow dyes according to the principle of chromogenic development. These color coupiers are preferably used in the blue-sensitive component layer of multiple-layer color photographic materials containing silver halide as the photosensitive substance.

As already known, derivatives of benzylacetanilide are mainly used as color couplers for the aforementioned purpose. The properties of the couplers, and of the dyes formed from them, can be influenced within wide limits by suitable substituents at various positions in the molecule. Thus, the introduction of relatively long hydrocarbon radicals makes the compounds resistant to diffusion, so that they can be embedded in the blue-sensitive component layer of the multiple-layer colour material. The effect of introducing a sulfo group or carboxyl group into the molecule is that the colour couplers can be added to the silver halide emulsion in the form of water-soluble alkali metal salts. The effect of substitution of the reactive methylene group with halogen, or any other radical which can be split off during color coupling, is that only two molecules of silver halide, rather than four, are required for dye formation (the color couplers are then so-called Z-equivalent couplers). Finally, other substituents may be necessary in order to improve the photographic properties of the coupler and of the dye formed therefrom.

The present invention relates to diffusion-resistant water-insoluble yellow couplers which are used in dispersed form. The requirements which must be satisfied by couplers such as these are extremely varied, the following being mentioned by way of example: high solubility in certain organic solvents and a relatively low melting point with a consequent high dispersibility in water or gelatin solution; high resistance to diffusion, stability of the coupler against climatic influences during storage ofthe finished color materials; limited influence upon the photographic properties of the silver halide; high reactivity during color development; favourable spectral properties of the developed dye; and resistance of the image dye to light and climatic influences. Last but not least, the coupler should be easy to prepare, thus minimising production costs.

It now has been found that benzoylacetanilides having the general formula (I) are eminently suitable for the production of yellow coupler images:

wherein:

R, represents a diffusion-inhibiting radical in the form of a linear or branched hydrocarbon chain having at least carbon atoms; I

X represents hydrogen or a radical which can be split off during colour coupling, mostly chlorine;

R represents halogen, cyano, R 0R CF COOR CONH COM- R CON(R S0 R SO NH SOzNHRg, SO2N(R3)2, 0r

and if two or more radicals R are present, they can be the same or different;

R represents alkyl having l to 4 carbon atoms or aryl, and iftwo groups R occur in the same radical, they can be the same or different; and

n represents 1, 2 or 3.

The particular characteristic of these couplers is the presence of a diffusion-inhibiting radical in the form of a long-chain alkoxy group in the ortho-position of the benzoyl radical. Couplers in which one group R represents a chlorine atom in the ortho-position, are particularly suitable. Accordingly, couplers of this kind have the formula (II):

in which R R X and n have the meanings given above. The effectiveness of couplers used according to the invention results in conjunction with the aforementioned substituents in the anilide portion. This is particularly true as regards 2-equivalent couplers having chlorine as the separable radical.

Large numbers of dispersable couplers in which the diffusion-inhibiting radical is linked otherwise then through an O-atom to the molecule, or is attached anywhere to the molecule, have previously been described. Compared with the substances used according to the invention, all these couplers show a greater tendency towards crystallisation and, for this reason, they can often only be used in conjunction with oil formers. Although this disadvantage can be obviated by introducing a water-solubilising group (for example a sulfo group) into the molecule, this measure has an adverse effect upon the spectral properties of the image dyes developed therefrom, since it displaces absorption towards longer wavelengths, and at the same time the definition of the color image is impaired.

The favourable effect of ortho-methoxy substitution in the benzoyl radical upon the spectral properties of the image dyes is also known. This is described in US. Pat. No. 2,728,658 to McCrossen et al. This has not, however, acquired any real practical significance because numerous preparative difficulties are involved in producing the o-methoxybenzoyl-acetic esters.

Comparison of the couplers used according to the invention, with couplers in which an alkoxy group is situated in the para-position of the benzoyl radical, is of particular significance. This para-alkoxy substitution leads to extremely active couplers which have, however, disadvantages in comparison with the couplers used according to the invention, including longer-wave absorption of the developed dyes and lower solubility, for example in ethyl acetate. The melting points of couplers having a long-chain alkoxy substituent in the para-position are from 10 to 40C higher than the melting points of the corresponding couplers with the long-chain alkoxy substituents in the ortho-position. Because of this property, these para-alkoxy couplers are more difficult to disperse, in addition to which they crystallise more readily from dispersions. In addition 2-equivalent couplers produced from couplers such as 3,849,140 3 4 these generally show a tendency towards heavy yellow Cl fogging. When a water-solubilising group is introduced ,c into para-alkoxybenzoyl couplers, an unfavourable displacement of the absorption maximum of the dyes towards longer wavelengths is obtained in this instance C1 also.

The following are examples of the couplers used according to the invention: 9 Q COCH -C0-NH- QCO-CH CO-NH-@ 10 10. -COCH-CON'H- 2 Q-CO-CH-CO-NH-Q 00 a CN 14 29 oc n c1 11. -CO-CH2-CO-NH-Q l 3 0 -CO-CH2-CONH- M) 14 29 c1 35 21 4, CQ J}H CO NH Q l2 Q CO-CH-CO-NHQ 06 11 Br 0C H CH3 OCH 62 co c11 cc .1111 x (:1

l @co-cra co mi The process for producing the new couplers is known in principle and comprises reacting suitably substituted aniline derivatives with long-chain o-alkoxybenzoylacctic esters. It is worth noting that these esters can be produced relatively easily compared with o-methoxy-benzoylacetic esters which are much more difficult to obtain. The coupler obtained can be subsequently converted into a 2-equivalent coupler, also by known methods.

The new couplers can readily be introduced into a silver halide emulsion. The dispersions are prepared by known methods. The most common method is to prepare a solution in water or gelatin solution with the assistance of a suitable wetting agent, and then to evaporate off the solvent. If necessary, a so-called oil former can be added in order to prevent crystallisation. There is, however, generally no need to do this with the couplers according to the invention, because of their particularly high dispersibility. The disadvantages of using oil formers are known.

The new yellow couplers react really well with the oxidation products of all conventional developers of the p-phenylene diamine type, for example N,N-diethyl-p-phenylene diamine (CD 1 N,N-diethyl- 3-methyl-p-phenylene diamine (CD 2), 4-amino-3 lengths. Secondary absorption in the green region of the spectrum is minimal.

The properties of the 2-equivalent couplers used ac-' cording to the invention, especially with chlorine as the separa bleradical, are particularly remarkable. During color development, these couplers cause little or no color fogging, a property which distinguishes them with advantage from most of the 2-equivalent couplers which have been described. The components according to the invention can be used both in the negativepositive process and also in the reversal process. Both film and paper can be used as layer substrate for the layers.

Representative couplers according to the invention can be prepared as follows: 1. Coupler 13 a. Methyl Z-tetradecyloxybenzoate 23 g of sodium metal were dissolved in 500 ml of ethylene glycol monomethylether, followed by the addition of a solution of 125 g of methyl salicylate in 400 ml of ethylene glycol monomethylether. The resulting mixture was then brought to boiling while stirring, followed by the dropwise addition of 277 g of tetradecyl bromide over a period of 3 hours. The mixture was then boiled for another hour, after which it was left to cool.

After stirring into 3 l i tres of water, the oil whic h precipitated was taken up in ether, and the ethereal solution was dried and evaporated, leaving behind a brown oil which was distilled in vacuo.

B.p. (H5 198- 199C. Yield: 213 g (61% of the theoretical) b. 2-tetradecyloxybenzoic acid 213 g of methyl Z-tetradecyloxybenzoate were dissolved in 500 ml of ethanol. followed by the addition of a solution of 91 g of pottasium hydroxide in ml of water. After boiling under reflux for 1 hour, the mixture was stirred into 3 litres of water and acidified with 10% by weight hydrochloric acid.

The acid which was precipitated was filtered under suction and washed with water. Recrystallization from methanol gave 163 g (80% of the theoretical) of pure acid. M.P. 51C.

c. Z-tetradecyloxybenzoyl chloride 162 g of acid were fused and ml of thionyl chloride were added in portions to the resulting melt. The reaction mixture was heated until the internal temperature had reached 100C.

Excess thionyl chloride was then distilled off in vacuo The acid chloride solidified.

Yield: 166 g (97% of the theoretical) Mp. 34 35C. d. a-(2*tetradecyloxybenzoyl) acetoacetic ethyl ester 173 g of the acid chloride dissolved in 50 m1 of benzene were added with stirring to g of sodium acetoacetic ethyl ester suspended in 50 ml of benzene. After boiling for 3 hours, the benzene was evaporated off} and the residue was poured into 2 litres ofice water and acidified with by weight hydrochloric acid. The oil which was precipitated was extracted with ether, and the ethereal solution was washed, dried and evaporated. Yield: 198 g (90% of the theroetical) M.p. 44 45C. e. Methyl 2-tetradecyloxybenzoyl-acetate 251 g of a-(2-tetradecyloxybenzoyl) acetoacetic ethyl ester, 135 g of 30% by weight sodium methoxide solution and 120 ml of methanol were boiled for 2.5 hours. After standing overnight, the mixture was poured into 2 litres of water, acidified and extracted with ether.

Evaporation of the ethereal solution left 193 g of ester, (96% of the theoretical) M.p. 40 41C.

f. 2-tetradecyloxybenzoyl-4'-methyl-acetanilide 10.7 g of 4-aminotoluene (p-toluidine) and 39.0 g of methyl 2-tetradecyloxybenzoyl-acetate were boiled for 6 hours in 100 ml of xylene, the alcohol which was eliminated (CH OH) being distilled off through a short column.

The residue was then dissolved hot in 500 ml of methanol, filtered and left to crystallize.

' Yield: 37.9 g M.p. 92 93C 2. Coupler 14 2-tetradecyloxybenzoyl-4'-methyl-chloroacetanilide 5.2 g of sulfuryl chloride dissolved in ml of chloroform were added dropwise over a period of minutes, while stirring and cooling with ice water (2C), to 18 g of coupler l3 dissolved in 200 ml of chloroform. The mixture was then stirred for 1 hour in ice water, and then for a further hour at room temperature.

The chloroform was evaporated off in vacuo and the residue-was recrystallized from 300 ml of methanol. Yield: 14 g M.p. 95 97C.

Chlorine determination:

found 6.9% Cl calculated 7.1% Cl 3. Coupler 17 2-tetradecyloxybenzoyl-2-methoxy-acetanilide This coupler was prepared in accordance with Specification 1f, except that 13.5 g of o-anisidine were used instead of the 4-amino toluene.

Yield: 22.4 g M.p. 58 60C. 4. Coupler 18 2-tetradecyloxybenzoyl-2'-methoxy-chloroacetanilide This coupler was prepared in accordance with Specification 2, except that, instead of coupler 13, 24.2 g of. coupler 17 were reacted with 6.75 g of sulfuryl chloride.

Yield: 23.4 g 5. Coupler l9 Z-tetradecyloxybenzoyl-Z-methoxy-fluoroacetanilide A three-necked flask equipped with stirring mechanism, thermometer and gas-inlet pipe, was filled with 300 ml of methanol. The methanol was cooled to -C with acetone/dry ice. Perchloryl fluoride was then introduced until the methanol contained 5.5 g of perchloryl fluoride.

A solution of 24 g of coupler 17 in 125 ml of methanol 9,1 g of 30% by weight sodium methoxid solution were run into the aforementioned perchloryl fluoride solution over a period of 30 minutes at -30C. The temperature was kept at -20C.

After 15 minutes, 300 g of ice water were added and M.p. 43 45C.

the coupler that waspreer tataw'as filtered off under suction, washed with water, and recrystallized twice- 14 from methanol. Yield: 18.4 g M.p. 56 57C marri'aetenfiinafibn;

methanol and the resulting solution was poured into i 300 ml ofice water. The oil that was precipitated solidified when triturated with a little methanol.

6 g of coupler were obtained after two recyrstallizations from methanol. M.p. 59 64C. 7. Coupler 41 2-tetradecyloxybenzoyl-2'-chloro-5'-N-methyl myl-acetanilide This coupler was prepared in accordance with Specification 1f, except that 22 g of 2-chloro-5-N-methylsulsulfa- Y ield: 40 g M.p. 92C;

8. Coupler 42 Z-tetradecyloxybenzoyl-Z'-chloro-5 '-N-methylsulfamylchloroacetanilide This coupler was prepared in accordance with Specification 2, except that, instead of coupler 13, 29 g of coupler 41 were reacted with 6.75 g of sulfuryl chloride. Yield: 23.4 g M.p. 84 86C.

Chlorine determination:

11.56% Cl calculated 11.3% C1 found 9. Coupler 48 2-tetradecyloxybenzoyl-4-methylsulfonyl-acetanilide This coupler was prepared in accordance with Specification 1f, except that 17.1 g of 4-methylsulfonylaniline were used instead of 4-amino-toluene. Yield: 35 g M.p. 79 80C. 19. Coupler 49 into ml of 7.5% by weight gelatin solution containing 0.25 g of sodium dodecylbenzene sulfonate. Dispersion time was 2 minutes, a Kotthoff mixing siren being used for dispersion. The ethyl acetate was evaporated off on a water bath. This dispersion could be stored for several days without change, either in liquid form or in solid form. b. Photographic application.

The above dispersion was added to 50 g ofa negative emulsion. The silver content, expressed as AgNO was 49 m ftzll winsssditia Qt s usual s s d tives, the emulsion was cast onto a layersubstrate and dried. Thereafter, samples were exposed under a step wedge (blue filter) both fresh and after cold storage (for 7 days at -C). The samples were subjected to a negative development process (developer substances diethyl-p-phenylene diamine). The following measurements were obtained:

The following Table shows the absorption maxima of the dyes obtained from coupler 17 with different developer substances, mentioned in the description.

nm CD 1 420 CD 2 427 CD 3 425 T 60 422 0. Comparison test with the coupler:

In this coupler, the two alkyl radicals have been interchanged compared to coupler 17 used according to the invention. The dispersion was prepared and the photo-' graphic emulsion was applied as in (a) and (b). The following measurements were obtained:

relative sensitivity density fogging fresh 100 1.40 0.12 after cold storage 60 0.98 0.10

In contrast to (b), a marked reduction in sensitivity and density is observed after cold storage in this instance. This is attributable to crystallization of the coupler.

EXAMPLE 2 a. A dispersion was prepared from 2.06 g of coupler 18 in the manner described in Example la.

b. In contrast to lb the emulsion used contained only 2.04 g of silver (Z-equivalent coupler). Samples of the finished layer were exposed and developed, both fresh and after cold storage under tropical conditions (for 7 days at 35C/85% relative humidity). The developer substance was again CD 1. The following measurements were obtained:

c. Comparison test with the coupler:

l O CH:

according to the British Pat. No. 733,260.

This coupler had the tetradecyloxy group in the para.

position. Treatment as in 2a and 2b gave the following results:

I relative sensitivity density fogging fresh 100 1.79 0.63 15 tropical storage 110 1.76 0.55

in contrast to coupler 18 used according to the invention, this coupler is remarkable for the high fogging levels of the fresh and stored materials. Absorption maxima and secondary color densities Abs. Mux. Absorption 7!) (nm) blue green red CD l 43l 100 7 3 CD 2 Mi I00 3 0 CD 3 438 I00 4 0 T 60 436 I00 8 2 It is clear from this Table that the dyes have unfavourable spectral properties.

What we claim is:

least one silver halide emulsion layer containing a yellow coupler of the formula I (R2 n h in which R represents a linear or branched hydrocarbon chain having at least 10 carbon atoms;

X represents chlorine;

R represents halogen, cyano, R OR -COOR -CONH CONHR CON(R SO R SO NH SO NHR -SO N(R or SO F, and if two or more groups R are present, they can be the same or different;

R represents alkyl having 1 to 4 carbon atoms or aryl, and if two groups R occur in the same radical, they can be the same or different; and

n represents 1, 2 or 3.

2. A color photographic material as claimed in claim 1 wherein the yellow coupler has the formula R 6R1 (in 2) l in which. R R X and n have the meanings given in claim 1.

3. Color photographic material as claimed in claim 1 I which has a plurality of emulsion layers, the yellow coupler being present in the blue-sensitive layer.

l. A color photographic material which comprises at 

1. A COLOR PHOTOGRAPHIC MATERIAL WHEN COMPRISES AT LEAST ONE SILVER HALIDE EMULSION LAYER CONTAINING A YELLOW COUPLER OF THE FORMULA
 2. A color photographic material as claimed in claim 1 wherein the yellow coupler has the formula
 3. Color photographic material as claimed in claim 1 which has a plurality of emulsion layers, the yellow coupler being present in the blue-sensitive layer. 